Dual Tank Fuel System for LS Swap

[Jetdr]

First post so go easy on me. I have spent days looking for the answer and lots of time and effort under the truck.

I have an 86 SWB with a 6.0 and 4L80. I decided I wanted to get rid of the the troublesome inline fuel pump. I purchased two 87 Fuel Sender Units and I installed two Walbro GSS 340 255 LPH pumps. I replaced all the fuel lines. I purchased the heavy duty 65PSI capable fuel selector valve (seems to be the highest rated selector valve available) and got all of this installed. I wired up the pumps to work through the tank selector switch (also an 87 switch) through relays to work with the ECM. All of the system work great EXCEPT the fuel selector valve. I think the selector valve is not heavy duty enough to over come the fuel pressure. While driving the truck the fuel returns to to the opposite tank the switch is on (sometimes not as bad as other times). Before everyone thinks i have it plumb wrong, believe me i have taken the tanks out 4 times to make sure. The right tank is plumb to the outer most two nipples and the left tank is plumbed to the inner most nipples (looking from under the truck with the fuel selector valve installed on the frame). Does anyone have any suggestions on a higher rated pressure fuel selector valve? I saw a few post from a while ago about a valve that was bought through JC Witney that was rated to 80 PSI. I called them yesterday and they says its not available anymore. The problem has to be with the fuel valve.

Thanks in advance!

[mongocanfly]

I dunno..gnaw on this for awhile...http://67-72chevytrucks.com/vboard/s...d.php?t=379708